ptp: Add a ptp clock driver for IDT ClockMatrix.

The IDT ClockMatrix (TM) family includes integrated devices that provide
eight PLL channels.  Each PLL channel can be independently configured as a
frequency synthesizer, jitter attenuator, digitally controlled
oscillator (DCO), or a digital phase lock loop (DPLL).  Typically
these devices are used as timing references and clock sources for PTP
applications.  This patch adds support for the device.

Co-developed-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Vincent Cheng <vincent.cheng.xh@renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1425 insertions, 0 deletions

diff --git a/drivers/ptp/ptp_clockmatrix.c b/drivers/ptp/ptp_clockmatrix.c
new file mode 100644
index 000000000000..cf5889b7d825
--- /dev/null
+++ b/drivers/ptp/ptp_clockmatrix.c
@@ -0,0 +1,1425 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * PTP hardware clock driver for the IDT ClockMatrix(TM) family of timing and
+ * synchronization devices.
+ *
+ * Copyright (C) 2019 Integrated Device Technology, Inc., a Renesas Company.
+ */
+#include <linux/firmware.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/ptp_clock_kernel.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/timekeeping.h>
+
+#include "ptp_private.h"
+#include "ptp_clockmatrix.h"
+
+MODULE_DESCRIPTION("Driver for IDT ClockMatrix(TM) family");
+MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
+MODULE_AUTHOR("IDT support-1588 <IDT-support-1588@lm.renesas.com>");
+MODULE_VERSION("1.0");
+MODULE_LICENSE("GPL");
+
+#define SETTIME_CORRECTION (0)
+
+static int char_array_to_timespec(u8 *buf,
+				  u8 count,
+				  struct timespec64 *ts)
+{
+	u8 i;
+	u64 nsec;
+	time64_t sec;
+
+	if (count < TOD_BYTE_COUNT)
+		return 1;
+
+	/* Sub-nanoseconds are in buf[0]. */
+	nsec = buf[4];
+	for (i = 0; i < 3; i++) {
+		nsec <<= 8;
+		nsec |= buf[3 - i];
+	}
+
+	sec = buf[10];
+	for (i = 0; i < 5; i++) {
+		sec <<= 8;
+		sec |= buf[9 - i];
+	}
+
+	ts->tv_sec = sec;
+	ts->tv_nsec = nsec;
+
+	return 0;
+}
+
+static int timespec_to_char_array(struct timespec64 const *ts,
+				  u8 *buf,
+				  u8 count)
+{
+	u8 i;
+	s32 nsec;
+	time64_t sec;
+
+	if (count < TOD_BYTE_COUNT)
+		return 1;
+
+	nsec = ts->tv_nsec;
+	sec = ts->tv_sec;
+
+	/* Sub-nanoseconds are in buf[0]. */
+	buf[0] = 0;
+	for (i = 1; i < 5; i++) {
+		buf[i] = nsec & 0xff;
+		nsec >>= 8;
+	}
+
+	for (i = 5; i < TOD_BYTE_COUNT; i++) {
+
+		buf[i] = sec & 0xff;
+		sec >>= 8;
+	}
+
+	return 0;
+}
+
+static int idtcm_xfer(struct idtcm *idtcm,
+		      u8 regaddr,
+		      u8 *buf,
+		      u16 count,
+		      bool write)
+{
+	struct i2c_client *client = idtcm->client;
+	struct i2c_msg msg[2];
+	int cnt;
+
+	msg[0].addr = client->addr;
+	msg[0].flags = 0;
+	msg[0].len = 1;
+	msg[0].buf = &regaddr;
+
+	msg[1].addr = client->addr;
+	msg[1].flags = write ? 0 : I2C_M_RD;
+	msg[1].len = count;
+	msg[1].buf = buf;
+
+	cnt = i2c_transfer(client->adapter, msg, 2);
+
+	if (cnt < 0) {
+		dev_err(&client->dev, "i2c_transfer returned %d\n", cnt);
+		return cnt;
+	} else if (cnt != 2) {
+		dev_err(&client->dev,
+			"i2c_transfer sent only %d of %d messages\n", cnt, 2);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int idtcm_page_offset(struct idtcm *idtcm, u8 val)
+{
+	u8 buf[4];
+	int err;
+
+	if (idtcm->page_offset == val)
+		return 0;
+
+	buf[0] = 0x0;
+	buf[1] = val;
+	buf[2] = 0x10;
+	buf[3] = 0x20;
+
+	err = idtcm_xfer(idtcm, PAGE_ADDR, buf, sizeof(buf), 1);
+
+	if (err)
+		dev_err(&idtcm->client->dev, "failed to set page offset\n");
+	else
+		idtcm->page_offset = val;
+
+	return err;
+}
+
+static int _idtcm_rdwr(struct idtcm *idtcm,
+		       u16 regaddr,
+		       u8 *buf,
+		       u16 count,
+		       bool write)
+{
+	u8 hi;
+	u8 lo;
+	int err;
+
+	hi = (regaddr >> 8) & 0xff;
+	lo = regaddr & 0xff;
+
+	err = idtcm_page_offset(idtcm, hi);
+
+	if (err)
+		goto out;
+
+	err = idtcm_xfer(idtcm, lo, buf, count, write);
+out:
+	return err;
+}
+
+static int idtcm_read(struct idtcm *idtcm,
+		      u16 module,
+		      u16 regaddr,
+		      u8 *buf,
+		      u16 count)
+{
+	return _idtcm_rdwr(idtcm, module + regaddr, buf, count, false);
+}
+
+static int idtcm_write(struct idtcm *idtcm,
+		       u16 module,
+		       u16 regaddr,
+		       u8 *buf,
+		       u16 count)
+{
+	return _idtcm_rdwr(idtcm, module + regaddr, buf, count, true);
+}
+
+static int _idtcm_gettime(struct idtcm_channel *channel,
+			  struct timespec64 *ts)
+{
+	struct idtcm *idtcm = channel->idtcm;
+	u8 buf[TOD_BYTE_COUNT];
+	u8 trigger;
+	int err;
+
+	err = idtcm_read(idtcm, channel->tod_read_primary,
+			 TOD_READ_PRIMARY_CMD, &trigger, sizeof(trigger));
+	if (err)
+		return err;
+
+	trigger &= ~(TOD_READ_TRIGGER_MASK << TOD_READ_TRIGGER_SHIFT);
+	trigger |= (1 << TOD_READ_TRIGGER_SHIFT);
+	trigger |= TOD_READ_TRIGGER_MODE;
+
+	err = idtcm_write(idtcm, channel->tod_read_primary,
+			  TOD_READ_PRIMARY_CMD, &trigger, sizeof(trigger));
+
+	if (err)
+		return err;
+
+	if (idtcm->calculate_overhead_flag)
+		idtcm->start_time = ktime_get_raw();
+
+	err = idtcm_read(idtcm, channel->tod_read_primary,
+			 TOD_READ_PRIMARY, buf, sizeof(buf));
+
+	if (err)
+		return err;
+
+	err = char_array_to_timespec(buf, sizeof(buf), ts);
+
+	return err;
+}
+
+static int _sync_pll_output(struct idtcm *idtcm,
+			    u8 pll,
+			    u8 sync_src,
+			    u8 qn,
+			    u8 qn_plus_1)
+{
+	int err;
+	u8 val;
+	u16 sync_ctrl0;
+	u16 sync_ctrl1;
+
+	if ((qn == 0) && (qn_plus_1 == 0))
+		return 0;
+
+	switch (pll) {
+	case 0:
+		sync_ctrl0 = HW_Q0_Q1_CH_SYNC_CTRL_0;
+		sync_ctrl1 = HW_Q0_Q1_CH_SYNC_CTRL_1;
+		break;
+	case 1:
+		sync_ctrl0 = HW_Q2_Q3_CH_SYNC_CTRL_0;
+		sync_ctrl1 = HW_Q2_Q3_CH_SYNC_CTRL_1;
+		break;
+	case 2:
+		sync_ctrl0 = HW_Q4_Q5_CH_SYNC_CTRL_0;
+		sync_ctrl1 = HW_Q4_Q5_CH_SYNC_CTRL_1;
+		break;
+	case 3:
+		sync_ctrl0 = HW_Q6_Q7_CH_SYNC_CTRL_0;
+		sync_ctrl1 = HW_Q6_Q7_CH_SYNC_CTRL_1;
+		break;
+	case 4:
+		sync_ctrl0 = HW_Q8_CH_SYNC_CTRL_0;
+		sync_ctrl1 = HW_Q8_CH_SYNC_CTRL_1;
+		break;
+	case 5:
+		sync_ctrl0 = HW_Q9_CH_SYNC_CTRL_0;
+		sync_ctrl1 = HW_Q9_CH_SYNC_CTRL_1;
+		break;
+	case 6:
+		sync_ctrl0 = HW_Q10_CH_SYNC_CTRL_0;
+		sync_ctrl1 = HW_Q10_CH_SYNC_CTRL_1;
+		break;
+	case 7:
+		sync_ctrl0 = HW_Q11_CH_SYNC_CTRL_0;
+		sync_ctrl1 = HW_Q11_CH_SYNC_CTRL_1;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	val = SYNCTRL1_MASTER_SYNC_RST;
+
+	/* Place master sync in reset */
+	err = idtcm_write(idtcm, 0, sync_ctrl1, &val, sizeof(val));
+	if (err)
+		return err;
+
+	err = idtcm_write(idtcm, 0, sync_ctrl0, &sync_src, sizeof(sync_src));
+	if (err)
+		return err;
+
+	/* Set sync trigger mask */
+	val |= SYNCTRL1_FBDIV_FRAME_SYNC_TRIG | SYNCTRL1_FBDIV_SYNC_TRIG;
+
+	if (qn)
+		val |= SYNCTRL1_Q0_DIV_SYNC_TRIG;
+
+	if (qn_plus_1)
+		val |= SYNCTRL1_Q1_DIV_SYNC_TRIG;
+
+	err = idtcm_write(idtcm, 0, sync_ctrl1, &val, sizeof(val));
+	if (err)
+		return err;
+
+	/* Place master sync out of reset */
+	val &= ~(SYNCTRL1_MASTER_SYNC_RST);
+	err = idtcm_write(idtcm, 0, sync_ctrl1, &val, sizeof(val));
+
+	return err;
+}
+
+static int idtcm_sync_pps_output(struct idtcm_channel *channel)
+{
+	struct idtcm *idtcm = channel->idtcm;
+
+	u8 pll;
+	u8 sync_src;
+	u8 qn;
+	u8 qn_plus_1;
+	int err = 0;
+
+	u16 output_mask = channel->output_mask;
+
+	switch (channel->dpll_n) {
+	case DPLL_0:
+		sync_src = SYNC_SOURCE_DPLL0_TOD_PPS;
+		break;
+	case DPLL_1:
+		sync_src = SYNC_SOURCE_DPLL1_TOD_PPS;
+		break;
+	case DPLL_2:
+		sync_src = SYNC_SOURCE_DPLL2_TOD_PPS;
+		break;
+	case DPLL_3:
+		sync_src = SYNC_SOURCE_DPLL3_TOD_PPS;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	for (pll = 0; pll < 8; pll++) {
+
+		qn = output_mask & 0x1;
+		output_mask = output_mask >> 1;
+
+		if (pll < 4) {
+			/* First 4 pll has 2 outputs */
+			qn_plus_1 = output_mask & 0x1;
+			output_mask = output_mask >> 1;
+		} else {
+			qn_plus_1 = 0;
+		}
+
+		if ((qn != 0) || (qn_plus_1 != 0))
+			err = _sync_pll_output(idtcm, pll, sync_src, qn,
+					       qn_plus_1);
+
+		if (err)
+			return err;
+	}
+
+	return err;
+}
+
+static int _idtcm_set_dpll_tod(struct idtcm_channel *channel,
+			       struct timespec64 const *ts,
+			       enum hw_tod_write_trig_sel wr_trig)
+{
+	struct idtcm *idtcm = channel->idtcm;
+
+	u8 buf[TOD_BYTE_COUNT];
+	u8 cmd;
+	int err;
+	struct timespec64 local_ts = *ts;
+	s64 total_overhead_ns;
+
+	/* Configure HW TOD write trigger. */
+	err = idtcm_read(idtcm, channel->hw_dpll_n, HW_DPLL_TOD_CTRL_1,
+			 &cmd, sizeof(cmd));
+
+	if (err)
+		return err;
+
+	cmd &= ~(0x0f);
+	cmd |= wr_trig | 0x08;
+
+	err = idtcm_write(idtcm, channel->hw_dpll_n, HW_DPLL_TOD_CTRL_1,
+			  &cmd, sizeof(cmd));
+
+	if (err)
+		return err;
+
+	if (wr_trig  != HW_TOD_WR_TRIG_SEL_MSB) {
+
+		err = timespec_to_char_array(&local_ts, buf, sizeof(buf));
+
+		if (err)
+			return err;
+
+		err = idtcm_write(idtcm, channel->hw_dpll_n,
+				  HW_DPLL_TOD_OVR__0, buf, sizeof(buf));
+
+		if (err)
+			return err;
+	}
+
+	/* ARM HW TOD write trigger. */
+	cmd &= ~(0x08);
+
+	err = idtcm_write(idtcm, channel->hw_dpll_n, HW_DPLL_TOD_CTRL_1,
+			  &cmd, sizeof(cmd));
+
+	if (wr_trig == HW_TOD_WR_TRIG_SEL_MSB) {
+
+		if (idtcm->calculate_overhead_flag) {
+			total_overhead_ns =  ktime_to_ns(ktime_get_raw()
+							 - idtcm->start_time)
+					     + idtcm->tod_write_overhead_ns
+					     + SETTIME_CORRECTION;
+
+			timespec64_add_ns(&local_ts, total_overhead_ns);
+
+			idtcm->calculate_overhead_flag = 0;
+		}
+
+		err = timespec_to_char_array(&local_ts, buf, sizeof(buf));
+
+		if (err)
+			return err;
+
+		err = idtcm_write(idtcm, channel->hw_dpll_n,
+				  HW_DPLL_TOD_OVR__0, buf, sizeof(buf));
+	}
+
+	return err;
+}
+
+static int _idtcm_settime(struct idtcm_channel *channel,
+			  struct timespec64 const *ts,
+			  enum hw_tod_write_trig_sel wr_trig)
+{
+	struct idtcm *idtcm = channel->idtcm;
+	s32 retval;
+	int err;
+	int i;
+	u8 trig_sel;
+
+	err = _idtcm_set_dpll_tod(channel, ts, wr_trig);
+
+	if (err)
+		return err;
+
+	/* Wait for the operation to complete. */
+	for (i = 0; i < 10000; i++) {
+		err = idtcm_read(idtcm, channel->hw_dpll_n,
+				 HW_DPLL_TOD_CTRL_1, &trig_sel,
+				 sizeof(trig_sel));
+
+		if (err)
+			return err;
+
+		if (trig_sel == 0x4a)
+			break;
+
+		err = 1;
+	}
+
+	if (err)
+		return err;
+
+	retval = idtcm_sync_pps_output(channel);
+
+	return retval;
+}
+
+static int idtcm_set_phase_pull_in_offset(struct idtcm_channel *channel,
+					  s32 offset_ns)
+{
+	int err;
+	int i;
+	struct idtcm *idtcm = channel->idtcm;
+
+	u8 buf[4];
+
+	for (i = 0; i < 4; i++) {
+		buf[i] = 0xff & (offset_ns);
+		offset_ns >>= 8;
+	}
+
+	err = idtcm_write(idtcm, channel->dpll_phase_pull_in, PULL_IN_OFFSET,
+			  buf, sizeof(buf));
+
+	return err;
+}
+
+static int idtcm_set_phase_pull_in_slope_limit(struct idtcm_channel *channel,
+					       u32 max_ffo_ppb)
+{
+	int err;
+	u8 i;
+	struct idtcm *idtcm = channel->idtcm;
+
+	u8 buf[3];
+
+	if (max_ffo_ppb & 0xff000000)
+		max_ffo_ppb = 0;
+
+	for (i = 0; i < 3; i++) {
+		buf[i] = 0xff & (max_ffo_ppb);
+		max_ffo_ppb >>= 8;
+	}
+
+	err = idtcm_write(idtcm, channel->dpll_phase_pull_in,
+			  PULL_IN_SLOPE_LIMIT, buf, sizeof(buf));
+
+	return err;
+}
+
+static int idtcm_start_phase_pull_in(struct idtcm_channel *channel)
+{
+	int err;
+	struct idtcm *idtcm = channel->idtcm;
+
+	u8 buf;
+
+	err = idtcm_read(idtcm, channel->dpll_phase_pull_in, PULL_IN_CTRL,
+			 &buf, sizeof(buf));
+
+	if (err)
+		return err;
+
+	if (buf == 0) {
+		buf = 0x01;
+		err = idtcm_write(idtcm, channel->dpll_phase_pull_in,
+				  PULL_IN_CTRL, &buf, sizeof(buf));
+	} else {
+		err = -EBUSY;
+	}
+
+	return err;
+}
+
+static int idtcm_do_phase_pull_in(struct idtcm_channel *channel,
+				  s32 offset_ns,
+				  u32 max_ffo_ppb)
+{
+	int err;
+
+	err = idtcm_set_phase_pull_in_offset(channel, -offset_ns);
+
+	if (err)
+		return err;
+
+	err = idtcm_set_phase_pull_in_slope_limit(channel, max_ffo_ppb);
+
+	if (err)
+		return err;
+
+	err = idtcm_start_phase_pull_in(channel);
+
+	return err;
+}
+
+static int _idtcm_adjtime(struct idtcm_channel *channel, s64 delta)
+{
+	int err;
+	struct idtcm *idtcm = channel->idtcm;
+	struct timespec64 ts;
+	s64 now;
+
+	if (abs(delta) < PHASE_PULL_IN_THRESHOLD_NS) {
+		err = idtcm_do_phase_pull_in(channel, delta, 0);
+	} else {
+		idtcm->calculate_overhead_flag = 1;
+
+		err = _idtcm_gettime(channel, &ts);
+
+		if (err)
+			return err;
+
+		now = timespec64_to_ns(&ts);
+		now += delta;
+
+		ts = ns_to_timespec64(now);
+
+		err = _idtcm_settime(channel, &ts, HW_TOD_WR_TRIG_SEL_MSB);
+	}
+
+	return err;
+}
+
+static int idtcm_state_machine_reset(struct idtcm *idtcm)
+{
+	int err;
+	u8 byte = SM_RESET_CMD;
+
+	err = idtcm_write(idtcm, RESET_CTRL, SM_RESET, &byte, sizeof(byte));
+
+	if (!err)
+		msleep_interruptible(POST_SM_RESET_DELAY_MS);
+
+	return err;
+}
+
+static int idtcm_read_hw_rev_id(struct idtcm *idtcm, u8 *hw_rev_id)
+{
+	return idtcm_read(idtcm,
+			  GENERAL_STATUS,
+			  HW_REV_ID,
+			  hw_rev_id,
+			  sizeof(u8));
+}
+
+static int idtcm_read_bond_id(struct idtcm *idtcm, u8 *bond_id)
+{
+	return idtcm_read(idtcm,
+			  GENERAL_STATUS,
+			  BOND_ID,
+			  bond_id,
+			  sizeof(u8));
+}
+
+static int idtcm_read_hw_csr_id(struct idtcm *idtcm, u16 *hw_csr_id)
+{
+	int err;
+	u8 buf[2] = {0};
+
+	err = idtcm_read(idtcm, GENERAL_STATUS, HW_CSR_ID, buf, sizeof(buf));
+
+	*hw_csr_id = (buf[1] << 8) | buf[0];
+
+	return err;
+}
+
+static int idtcm_read_hw_irq_id(struct idtcm *idtcm, u16 *hw_irq_id)
+{
+	int err;
+	u8 buf[2] = {0};
+
+	err = idtcm_read(idtcm, GENERAL_STATUS, HW_IRQ_ID, buf, sizeof(buf));
+
+	*hw_irq_id = (buf[1] << 8) | buf[0];
+
+	return err;
+}
+
+static int idtcm_read_product_id(struct idtcm *idtcm, u16 *product_id)
+{
+	int err;
+	u8 buf[2] = {0};
+
+	err = idtcm_read(idtcm, GENERAL_STATUS, PRODUCT_ID, buf, sizeof(buf));
+
+	*product_id = (buf[1] << 8) | buf[0];
+
+	return err;
+}
+
+static int idtcm_read_major_release(struct idtcm *idtcm, u8 *major)
+{
+	int err;
+	u8 buf = 0;
+
+	err = idtcm_read(idtcm, GENERAL_STATUS, MAJ_REL, &buf, sizeof(buf));
+
+	*major = buf >> 1;
+
+	return err;
+}
+
+static int idtcm_read_minor_release(struct idtcm *idtcm, u8 *minor)
+{
+	return idtcm_read(idtcm, GENERAL_STATUS, MIN_REL, minor, sizeof(u8));
+}
+
+static int idtcm_read_hotfix_release(struct idtcm *idtcm, u8 *hotfix)
+{
+	return idtcm_read(idtcm,
+			  GENERAL_STATUS,
+			  HOTFIX_REL,
+			  hotfix,
+			  sizeof(u8));
+}
+
+static int idtcm_read_pipeline(struct idtcm *idtcm, u32 *pipeline)
+{
+	int err;
+	u8 buf[4] = {0};
+
+	err = idtcm_read(idtcm,
+			 GENERAL_STATUS,
+			 PIPELINE_ID,
+			 &buf[0],
+			 sizeof(buf));
+
+	*pipeline = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
+
+	return err;
+}
+
+static int process_pll_mask(struct idtcm *idtcm, u32 addr, u8 val, u8 *mask)
+{
+	int err = 0;
+
+	if (addr == PLL_MASK_ADDR) {
+		if ((val & 0xf0) || !(val & 0xf)) {
+			dev_err(&idtcm->client->dev,
+				"Invalid PLL mask 0x%hhx\n", val);
+			err = -EINVAL;
+		}
+		*mask = val;
+	}
+
+	return err;
+}
+
+static int set_pll_output_mask(struct idtcm *idtcm, u16 addr, u8 val)
+{
+	int err = 0;
+
+	switch (addr) {
+	case OUTPUT_MASK_PLL0_ADDR:
+		SET_U16_LSB(idtcm->channel[0].output_mask, val);
+		break;
+	case OUTPUT_MASK_PLL0_ADDR + 1:
+		SET_U16_MSB(idtcm->channel[0].output_mask, val);
+		break;
+	case OUTPUT_MASK_PLL1_ADDR:
+		SET_U16_LSB(idtcm->channel[1].output_mask, val);
+		break;
+	case OUTPUT_MASK_PLL1_ADDR + 1:
+		SET_U16_MSB(idtcm->channel[1].output_mask, val);
+		break;
+	case OUTPUT_MASK_PLL2_ADDR:
+		SET_U16_LSB(idtcm->channel[2].output_mask, val);
+		break;
+	case OUTPUT_MASK_PLL2_ADDR + 1:
+		SET_U16_MSB(idtcm->channel[2].output_mask, val);
+		break;
+	case OUTPUT_MASK_PLL3_ADDR:
+		SET_U16_LSB(idtcm->channel[3].output_mask, val);
+		break;
+	case OUTPUT_MASK_PLL3_ADDR + 1:
+		SET_U16_MSB(idtcm->channel[3].output_mask, val);
+		break;
+	default:
+		err = -EINVAL;
+		break;
+	}
+
+	return err;
+}
+
+static int check_and_set_masks(struct idtcm *idtcm,
+			       u16 regaddr,
+			       u8 val)
+{
+	int err = 0;
+
+	if (set_pll_output_mask(idtcm, regaddr, val)) {
+		/* Not an output mask, check for pll mask */
+		err = process_pll_mask(idtcm, regaddr, val, &idtcm->pll_mask);
+	}
+
+	return err;
+}
+
+static void display_pll_and_output_masks(struct idtcm *idtcm)
+{
+	u8 i;
+	u8 mask;
+
+	dev_dbg(&idtcm->client->dev, "pllmask = 0x%02x\n", idtcm->pll_mask);
+
+	for (i = 0; i < MAX_PHC_PLL; i++) {
+		mask = 1 << i;
+
+		if (mask & idtcm->pll_mask)
+			dev_dbg(&idtcm->client->dev,
+				"PLL%d output_mask = 0x%04x\n",
+				i, idtcm->channel[i].output_mask);
+	}
+}
+
+static int idtcm_load_firmware(struct idtcm *idtcm,
+			       struct device *dev)
+{
+	const struct firmware *fw;
+	struct idtcm_fwrc *rec;
+	u32 regaddr;
+	int err;
+	s32 len;
+	u8 val;
+	u8 loaddr;
+
+	dev_dbg(&idtcm->client->dev, "requesting firmware '%s'\n", FW_FILENAME);
+
+	err = request_firmware(&fw, FW_FILENAME, dev);
+
+	if (err)
+		return err;
+
+	dev_dbg(&idtcm->client->dev, "firmware size %zu bytes\n", fw->size);
+
+	rec = (struct idtcm_fwrc *) fw->data;
+
+	if (fw->size > 0)
+		idtcm_state_machine_reset(idtcm);
+
+	for (len = fw->size; len > 0; len -= sizeof(*rec)) {
+
+		if (rec->reserved) {
+			dev_err(&idtcm->client->dev,
+				"bad firmware, reserved field non-zero\n");
+			err = -EINVAL;
+		} else {
+			regaddr = rec->hiaddr << 8;
+			regaddr |= rec->loaddr;
+
+			val = rec->value;
+			loaddr = rec->loaddr;
+
+			rec++;
+
+			err = check_and_set_masks(idtcm, regaddr, val);
+		}
+
+		if (err == 0) {
+			/* Top (status registers) and bottom are read-only */
+			if ((regaddr < GPIO_USER_CONTROL)
+			    || (regaddr >= SCRATCH))
+				continue;
+
+			/* Page size 128, last 4 bytes of page skipped */
+			if (((loaddr > 0x7b) && (loaddr <= 0x7f))
+			     || ((loaddr > 0xfb) && (loaddr <= 0xff)))
+				continue;
+
+			err = idtcm_write(idtcm, regaddr, 0, &val, sizeof(val));
+		}
+
+		if (err)
+			goto out;
+	}
+
+	display_pll_and_output_masks(idtcm);
+
+out:
+	release_firmware(fw);
+	return err;
+}
+
+static int idtcm_pps_enable(struct idtcm_channel *channel, bool enable)
+{
+	struct idtcm *idtcm = channel->idtcm;
+	u32 module;
+	u8 val;
+	int err;
+
+	/*
+	 * This assumes that the 1-PPS is on the second of the two
+	 * output.  But is this always true?
+	 */
+	switch (channel->dpll_n) {
+	case DPLL_0:
+		module = OUTPUT_1;
+		break;
+	case DPLL_1:
+		module = OUTPUT_3;
+		break;
+	case DPLL_2:
+		module = OUTPUT_5;
+		break;
+	case DPLL_3:
+		module = OUTPUT_7;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	err = idtcm_read(idtcm, module, OUT_CTRL_1, &val, sizeof(val));
+
+	if (err)
+		return err;
+
+	if (enable)
+		val |= SQUELCH_DISABLE;
+	else
+		val &= ~SQUELCH_DISABLE;
+
+	err = idtcm_write(idtcm, module, OUT_CTRL_1, &val, sizeof(val));
+
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int idtcm_set_pll_mode(struct idtcm_channel *channel,
+			      enum pll_mode pll_mode)
+{
+	struct idtcm *idtcm = channel->idtcm;
+	int err;
+	u8 dpll_mode;
+
+	err = idtcm_read(idtcm, channel->dpll_n, DPLL_MODE,
+			 &dpll_mode, sizeof(dpll_mode));
+	if (err)
+		return err;
+
+	dpll_mode &= ~(PLL_MODE_MASK << PLL_MODE_SHIFT);
+
+	dpll_mode |= (pll_mode << PLL_MODE_SHIFT);
+
+	channel->pll_mode = pll_mode;
+
+	err = idtcm_write(idtcm, channel->dpll_n, DPLL_MODE,
+			  &dpll_mode, sizeof(dpll_mode));
+	if (err)
+		return err;
+
+	return 0;
+}
+
+/* PTP Hardware Clock interface */
+
+static int idtcm_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
+{
+	struct idtcm_channel *channel =
+		container_of(ptp, struct idtcm_channel, caps);
+	struct idtcm *idtcm = channel->idtcm;
+	u8 i;
+	bool neg_adj = 0;
+	int err;
+	u8 buf[6] = {0};
+	s64 fcw;
+
+	if (channel->pll_mode  != PLL_MODE_WRITE_FREQUENCY) {
+		err = idtcm_set_pll_mode(channel, PLL_MODE_WRITE_FREQUENCY);
+		if (err)
+			return err;
+	}
+
+	/*
+	 * Frequency Control Word unit is: 1.11 * 10^-10 ppm
+	 *
+	 * adjfreq:
+	 *       ppb * 10^9
+	 * FCW = ----------
+	 *          111
+	 *
+	 * adjfine:
+	 *       ppm_16 * 5^12
+	 * FCW = -------------
+	 *         111 * 2^4
+	 */
+	if (ppb < 0) {
+		neg_adj = 1;
+		ppb = -ppb;
+	}
+
+	/* 2 ^ -53 = 1.1102230246251565404236316680908e-16 */
+	fcw = ppb * 1000000000000ULL;
+
+	fcw = div_u64(fcw, 111022);
+
+	if (neg_adj)
+		fcw = -fcw;
+
+	for (i = 0; i < 6; i++) {
+		buf[i] = fcw & 0xff;
+		fcw >>= 8;
+	}
+
+	mutex_lock(&idtcm->reg_lock);
+
+	err = idtcm_write(idtcm, channel->dpll_freq, DPLL_WR_FREQ,
+			  buf, sizeof(buf));
+
+	mutex_unlock(&idtcm->reg_lock);
+	return err;
+}
+
+static int idtcm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
+{
+	struct idtcm_channel *channel =
+		container_of(ptp, struct idtcm_channel, caps);
+	struct idtcm *idtcm = channel->idtcm;
+	int err;
+
+	mutex_lock(&idtcm->reg_lock);
+
+	err = _idtcm_gettime(channel, ts);
+
+	mutex_unlock(&idtcm->reg_lock);
+
+	return err;
+}
+
+static int idtcm_settime(struct ptp_clock_info *ptp,
+			 const struct timespec64 *ts)
+{
+	struct idtcm_channel *channel =
+		container_of(ptp, struct idtcm_channel, caps);
+	struct idtcm *idtcm = channel->idtcm;
+	int err;
+
+	mutex_lock(&idtcm->reg_lock);
+
+	err = _idtcm_settime(channel, ts, HW_TOD_WR_TRIG_SEL_MSB);
+
+	mutex_unlock(&idtcm->reg_lock);
+
+	return err;
+}
+
+static int idtcm_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+	struct idtcm_channel *channel =
+		container_of(ptp, struct idtcm_channel, caps);
+	struct idtcm *idtcm = channel->idtcm;
+	int err;
+
+	mutex_lock(&idtcm->reg_lock);
+
+	err = _idtcm_adjtime(channel, delta);
+
+	mutex_unlock(&idtcm->reg_lock);
+
+	return err;
+}
+
+static int idtcm_enable(struct ptp_clock_info *ptp,
+			struct ptp_clock_request *rq, int on)
+{
+	struct idtcm_channel *channel =
+		container_of(ptp, struct idtcm_channel, caps);
+
+	switch (rq->type) {
+	case PTP_CLK_REQ_PEROUT:
+		if (!on)
+			return idtcm_pps_enable(channel, false);
+
+		/* Only accept a 1-PPS aligned to the second. */
+		if (rq->perout.start.nsec || rq->perout.period.sec != 1 ||
+		    rq->perout.period.nsec)
+			return -ERANGE;
+
+		return idtcm_pps_enable(channel, true);
+	default:
+		break;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int idtcm_enable_tod(struct idtcm_channel *channel)
+{
+	struct idtcm *idtcm = channel->idtcm;
+	struct timespec64 ts = {0, 0};
+	u8 cfg;
+	int err;
+
+	err = idtcm_pps_enable(channel, false);
+	if (err)
+		return err;
+
+	/*
+	 * Start the TOD clock ticking.
+	 */
+	err = idtcm_read(idtcm, channel->tod_n, TOD_CFG, &cfg, sizeof(cfg));
+	if (err)
+		return err;
+
+	cfg |= TOD_ENABLE;
+
+	err = idtcm_write(idtcm, channel->tod_n, TOD_CFG, &cfg, sizeof(cfg));
+	if (err)
+		return err;
+
+	return _idtcm_settime(channel, &ts, HW_TOD_WR_TRIG_SEL_MSB);
+}
+
+static void idtcm_display_version_info(struct idtcm *idtcm)
+{
+	u8 major;
+	u8 minor;
+	u8 hotfix;
+	u32 pipeline;
+	u16 product_id;
+	u16 csr_id;
+	u16 irq_id;
+	u8 hw_rev_id;
+	u8 bond_id;
+
+	idtcm_read_major_release(idtcm, &major);
+	idtcm_read_minor_release(idtcm, &minor);
+	idtcm_read_hotfix_release(idtcm, &hotfix);
+	idtcm_read_pipeline(idtcm, &pipeline);
+
+	idtcm_read_product_id(idtcm, &product_id);
+	idtcm_read_hw_rev_id(idtcm, &hw_rev_id);
+	idtcm_read_bond_id(idtcm, &bond_id);
+	idtcm_read_hw_csr_id(idtcm, &csr_id);
+	idtcm_read_hw_irq_id(idtcm, &irq_id);
+
+	dev_info(&idtcm->client->dev, "Version:  %d.%d.%d, Pipeline %u\t"
+		 "0x%04x, Rev %d, Bond %d, CSR %d, IRQ %d\n",
+		 major, minor, hotfix, pipeline,
+		 product_id, hw_rev_id, bond_id, csr_id, irq_id);
+}
+
+static struct ptp_clock_info idtcm_caps = {
+	.owner		= THIS_MODULE,
+	.max_adj	= 244000,
+	.n_per_out	= 1,
+	.adjfreq	= &idtcm_adjfreq,
+	.adjtime	= &idtcm_adjtime,
+	.gettime64	= &idtcm_gettime,
+	.settime64	= &idtcm_settime,
+	.enable		= &idtcm_enable,
+};
+
+static int idtcm_enable_channel(struct idtcm *idtcm, u32 index)
+{
+	struct idtcm_channel *channel;
+	int err;
+
+	if (!(index < MAX_PHC_PLL))
+		return -EINVAL;
+
+	channel = &idtcm->channel[index];
+
+	switch (index) {
+	case 0:
+		channel->dpll_freq = DPLL_FREQ_0;
+		channel->dpll_n = DPLL_0;
+		channel->tod_read_primary = TOD_READ_PRIMARY_0;
+		channel->tod_write = TOD_WRITE_0;
+		channel->tod_n = TOD_0;
+		channel->hw_dpll_n = HW_DPLL_0;
+		channel->dpll_phase = DPLL_PHASE_0;
+		channel->dpll_ctrl_n = DPLL_CTRL_0;
+		channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_0;
+		break;
+	case 1:
+		channel->dpll_freq = DPLL_FREQ_1;
+		channel->dpll_n = DPLL_1;
+		channel->tod_read_primary = TOD_READ_PRIMARY_1;
+		channel->tod_write = TOD_WRITE_1;
+		channel->tod_n = TOD_1;
+		channel->hw_dpll_n = HW_DPLL_1;
+		channel->dpll_phase = DPLL_PHASE_1;
+		channel->dpll_ctrl_n = DPLL_CTRL_1;
+		channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_1;
+		break;
+	case 2:
+		channel->dpll_freq = DPLL_FREQ_2;
+		channel->dpll_n = DPLL_2;
+		channel->tod_read_primary = TOD_READ_PRIMARY_2;
+		channel->tod_write = TOD_WRITE_2;
+		channel->tod_n = TOD_2;
+		channel->hw_dpll_n = HW_DPLL_2;
+		channel->dpll_phase = DPLL_PHASE_2;
+		channel->dpll_ctrl_n = DPLL_CTRL_2;
+		channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_2;
+		break;
+	case 3:
+		channel->dpll_freq = DPLL_FREQ_3;
+		channel->dpll_n = DPLL_3;
+		channel->tod_read_primary = TOD_READ_PRIMARY_3;
+		channel->tod_write = TOD_WRITE_3;
+		channel->tod_n = TOD_3;
+		channel->hw_dpll_n = HW_DPLL_3;
+		channel->dpll_phase = DPLL_PHASE_3;
+		channel->dpll_ctrl_n = DPLL_CTRL_3;
+		channel->dpll_phase_pull_in = DPLL_PHASE_PULL_IN_3;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	channel->idtcm = idtcm;
+
+	channel->caps = idtcm_caps;
+	snprintf(channel->caps.name, sizeof(channel->caps.name),
+		 "IDT CM PLL%u", index);
+
+	err = idtcm_set_pll_mode(channel, PLL_MODE_WRITE_FREQUENCY);
+	if (err)
+		return err;
+
+	err = idtcm_enable_tod(channel);
+	if (err)
+		return err;
+
+	channel->ptp_clock = ptp_clock_register(&channel->caps, NULL);
+
+	if (IS_ERR(channel->ptp_clock)) {
+		err = PTR_ERR(channel->ptp_clock);
+		channel->ptp_clock = NULL;
+		return err;
+	}
+
+	if (!channel->ptp_clock)
+		return -ENOTSUPP;
+
+	dev_info(&idtcm->client->dev, "PLL%d registered as ptp%d\n",
+		 index, channel->ptp_clock->index);
+
+	return 0;
+}
+
+static void ptp_clock_unregister_all(struct idtcm *idtcm)
+{
+	u8 i;
+	struct idtcm_channel *channel;
+
+	for (i = 0; i < MAX_PHC_PLL; i++) {
+
+		channel = &idtcm->channel[i];
+
+		if (channel->ptp_clock)
+			ptp_clock_unregister(channel->ptp_clock);
+	}
+}
+
+static void set_default_masks(struct idtcm *idtcm)
+{
+	idtcm->pll_mask = DEFAULT_PLL_MASK;
+
+	idtcm->channel[0].output_mask = DEFAULT_OUTPUT_MASK_PLL0;
+	idtcm->channel[1].output_mask = DEFAULT_OUTPUT_MASK_PLL1;
+	idtcm->channel[2].output_mask = DEFAULT_OUTPUT_MASK_PLL2;
+	idtcm->channel[3].output_mask = DEFAULT_OUTPUT_MASK_PLL3;
+}
+
+static int set_tod_write_overhead(struct idtcm *idtcm)
+{
+	int err;
+	u8 i;
+
+	s64 total_ns = 0;
+
+	ktime_t start;
+	ktime_t stop;
+
+	char buf[TOD_BYTE_COUNT];
+
+	struct idtcm_channel *channel = &idtcm->channel[2];
+
+	/* Set page offset */
+	idtcm_write(idtcm, channel->hw_dpll_n, HW_DPLL_TOD_OVR__0,
+		    buf, sizeof(buf));
+
+	for (i = 0; i < TOD_WRITE_OVERHEAD_COUNT_MAX; i++) {
+
+		start = ktime_get_raw();
+
+		err = idtcm_write(idtcm, channel->hw_dpll_n,
+				  HW_DPLL_TOD_OVR__0, buf, sizeof(buf));
+
+		if (err)
+			return err;
+
+		stop = ktime_get_raw();
+
+		total_ns += ktime_to_ns(stop - start);
+	}
+
+	idtcm->tod_write_overhead_ns = div_s64(total_ns,
+					       TOD_WRITE_OVERHEAD_COUNT_MAX);
+
+	return err;
+}
+
+static int idtcm_probe(struct i2c_client *client,
+		       const struct i2c_device_id *id)
+{
+	struct idtcm *idtcm;
+	int err;
+	u8 i;
+
+	/* Unused for now */
+	(void)id;
+
+	idtcm = devm_kzalloc(&client->dev, sizeof(struct idtcm), GFP_KERNEL);
+
+	if (!idtcm)
+		return -ENOMEM;
+
+	idtcm->client = client;
+	idtcm->page_offset = 0xff;
+	idtcm->calculate_overhead_flag = 0;
+
+	set_default_masks(idtcm);
+
+	mutex_init(&idtcm->reg_lock);
+	mutex_lock(&idtcm->reg_lock);
+
+	idtcm_display_version_info(idtcm);
+
+	err = set_tod_write_overhead(idtcm);
+
+	if (err)
+		return err;
+
+	err = idtcm_load_firmware(idtcm, &client->dev);
+
+	if (err)
+		dev_warn(&idtcm->client->dev,
+			 "loading firmware failed with %d\n", err);
+
+	if (idtcm->pll_mask) {
+		for (i = 0; i < MAX_PHC_PLL; i++) {
+			if (idtcm->pll_mask & (1 << i)) {
+				err = idtcm_enable_channel(idtcm, i);
+				if (err)
+					break;
+			}
+		}
+	} else {
+		dev_err(&idtcm->client->dev,
+			"no PLLs flagged as PHCs, nothing to do\n");
+		err = -ENODEV;
+	}
+
+	mutex_unlock(&idtcm->reg_lock);
+
+	if (err) {
+		ptp_clock_unregister_all(idtcm);
+		return err;
+	}
+
+	i2c_set_clientdata(client, idtcm);
+
+	return 0;
+}
+
+static int idtcm_remove(struct i2c_client *client)
+{
+	struct idtcm *idtcm = i2c_get_clientdata(client);
+
+	ptp_clock_unregister_all(idtcm);
+
+	mutex_destroy(&idtcm->reg_lock);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id idtcm_dt_id[] = {
+	{ .compatible = "idt,8a34000" },
+	{ .compatible = "idt,8a34001" },
+	{ .compatible = "idt,8a34002" },
+	{ .compatible = "idt,8a34003" },
+	{ .compatible = "idt,8a34004" },
+	{ .compatible = "idt,8a34005" },
+	{ .compatible = "idt,8a34006" },
+	{ .compatible = "idt,8a34007" },
+	{ .compatible = "idt,8a34008" },
+	{ .compatible = "idt,8a34009" },
+	{ .compatible = "idt,8a34010" },
+	{ .compatible = "idt,8a34011" },
+	{ .compatible = "idt,8a34012" },
+	{ .compatible = "idt,8a34013" },
+	{ .compatible = "idt,8a34014" },
+	{ .compatible = "idt,8a34015" },
+	{ .compatible = "idt,8a34016" },
+	{ .compatible = "idt,8a34017" },
+	{ .compatible = "idt,8a34018" },
+	{ .compatible = "idt,8a34019" },
+	{ .compatible = "idt,8a34040" },
+	{ .compatible = "idt,8a34041" },
+	{ .compatible = "idt,8a34042" },
+	{ .compatible = "idt,8a34043" },
+	{ .compatible = "idt,8a34044" },
+	{ .compatible = "idt,8a34045" },
+	{ .compatible = "idt,8a34046" },
+	{ .compatible = "idt,8a34047" },
+	{ .compatible = "idt,8a34048" },
+	{ .compatible = "idt,8a34049" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, idtcm_dt_id);
+#endif
+
+static const struct i2c_device_id idtcm_i2c_id[] = {
+	{ "8a34000" },
+	{ "8a34001" },
+	{ "8a34002" },
+	{ "8a34003" },
+	{ "8a34004" },
+	{ "8a34005" },
+	{ "8a34006" },
+	{ "8a34007" },
+	{ "8a34008" },
+	{ "8a34009" },
+	{ "8a34010" },
+	{ "8a34011" },
+	{ "8a34012" },
+	{ "8a34013" },
+	{ "8a34014" },
+	{ "8a34015" },
+	{ "8a34016" },
+	{ "8a34017" },
+	{ "8a34018" },
+	{ "8a34019" },
+	{ "8a34040" },
+	{ "8a34041" },
+	{ "8a34042" },
+	{ "8a34043" },
+	{ "8a34044" },
+	{ "8a34045" },
+	{ "8a34046" },
+	{ "8a34047" },
+	{ "8a34048" },
+	{ "8a34049" },
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, idtcm_i2c_id);
+
+static struct i2c_driver idtcm_driver = {
+	.driver = {
+		.of_match_table	= of_match_ptr(idtcm_dt_id),
+		.name		= "idtcm",
+	},
+	.probe		= idtcm_probe,
+	.remove		= idtcm_remove,
+	.id_table	= idtcm_i2c_id,
+};
+
+module_i2c_driver(idtcm_driver);